Electrical control apparatus



A ril 29, 1930. w. M. mwm 1,156,727

ELECTRI CAL CONTROL APPARATUS Fi led Sept. 3, 1926 INVENTOR.

BY a w A TTORNEY 916v Zbwwe v,

Patented Apr. 29, 1930 UNITED STATES PA-TENT OFFICE WILLIAM H. BROWER, OF PALO ALTO, CALIFORNIA, ASSIGNOR TO FEDERAL TELE- GRAPE COMPANY, OF SAN FRANCISCO, CALIFORNIA, A CORPORATION OF CALI- FORNIA ELECTRICAL CONTROL APPARATUS Application filed September 3, 1926. Serial No. 133,431.

My invention relates broadly to a control apparatus for electrical circuits and more particularly to a combined switching mechanism and rotatable adjustor for electrical apparatus.

taneously manipulated by an operator.

Another object of my invention is to provide a compact assembly of electrical mechanism and rotatable control unit where a switching mechanism is mounted on or in immediate association with the rotatable control device.

A further object of my invention is to provide a mechanical assembly of electrical apparatus wherein a single casting is provided for carrying a rotatable control apparatus and an electrical switching mechanism in association therewith in such manner that the rotatable control apparatus may be actuated from a point immediately adjacent the actuator for the electrical switching mechanism.

Still another object of my invention is to provide a compact apparatus assembly for mounting adjacent a panel through which a rotatable control shaft projects for actuation by a rotatable knob with a switching mechanism having a control lever arranged to swing in a circular path limited by the mechanical relation between the control lever and the rotatable control shaft.

My invention will be more clearly understood by reference to the accompanying drawings in which:

Figure 1 is a side elevation of the rotatable control apparatus and switching mechanism of my invention; Fig. 2 is a front view of the control apparatus of my invention with the panel thereof partially broken away to show the position of the control apparatus with respect to the panel; Fig. 3 is a plan view showing the assembly of the control apparatus of my invention; and Fig. 4 is a perspective view illustrating the parts of the switching mechanism which are mounted in immediate association with the rotatable control actuator.

In the assembly of radio broadcast receiving apparatus it is important to provide a minimum number of controls for the apparatus. At the same time it is necessary in order to secure maximum efliciency in the operation of the receiving circuits that provision be made for the accurate adjustment of the constants of the circuits. In providing .a plurality of adjustments for the circuits of a radio receiving system I have devised a construction of electrical switching mechanism and rotatable actuator which is capable of compact assembly and is practical in its manufacture and production.

In the drawings I have illustrated my invention in association with a variometer, although I desire that it be understood that. any rotatable device may be operated by the instrumentality of my invention, such as a variable condenser or other variable electrical or mechanical devices.

Referring to the drawings in more detail, reference character 1 represents a casting which supports the several parts of the apparatus of my invention. The casting 1 has laterally extending portions 2 and 3 at opposite ends thereof which form a support for the insulated plate member '11. The casting 1 has a central enlarged portion 4: in which is journaled the rotatable control shaft 5 which passes through the insulated panel 6 and plate member 7 for actuation by the knob 8. The shaft 5 carries the frame of the rotatable inductance device 9 variable with respect to the frame of the fixed inductance device 10 which is mounted on the insulated plate 11. A suitable projection 9 may be formed upon the frame 9 which is obstructed in its move ment by the inwardly directed lugs 2 or 3 on the latterally extending portions 2 and 3, respectively. I provide a spring device 22 for securing the rotatable shaft member in position. The insulated plate 11 provides a support for the vertically extending contact members 12, 13 and 14 which terminate in faces 1%, 13 and 14*. A second shaft member 15 is journaled in the enlarged portion 4 g of the casting l and carries a switch arm 20' at one end thereof having a face 2O arranged to sweep over the upper portions of contacts 12 13 and 14 For controlling the movement of the switch arm 20 I provide a lever member 17 which is enlarged intermediate its ends and secured at its extremity by means of screwv device 16 to the end of the shaft member 15. The lever member 17 is offset at its end as represented at 18 and is provided with insul'atedi knob t9 thereon. The en larged portion. of the lever 17 is provided with a substantially elliptically shaped aperture 21 through which the shaft 5 passes. The arrangement of the lever 17 with respect to the shaft 15 is such that the swinging movement of lever 17 is.- confined to. definite opposite limits by reason of abutment of the sides of the apertured portion, 21 of lever 1:7 with thesides of the shaft member 5.

The assembly of the switching mechanism and rotatableactuator is extremely compact such that the operator may manipulate the rotatable actuator and the switching lever simultaneously with. one hand in accurately adjusting the characteristics of the electrical circuit with which the device is actuated. I have shown. three positions of the switching lever, but it will be understood that any desired number of positions of the switching lever may be provided: and that. the number I have selected herein is merely for the purpose of illustration.

' While I have described my invention in one of its preferred embodiments, I desire that it be understood that modifications may be made and that no limitationsupon my in.- vention are intended other than. are imposed by the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent of the United: States. is as follows:

1. An. electrical control apparatuscomprising a, frame, a shaft member journaled in said frame, an insulated panel structure carried by said frame,aplurality of contacts supported on said panel structure, a switching. device journal'ed in said frame at a point remote from said shaft member, a; control lever for said switching device, said; control lever being angularly movable to a multiplicity of positions including opposite limiting positionsand an int rmediate position and. surroundingopposite sides of said. shaft men ber; and; limited at opposite ends of its. path of, movementby abutment with said shaft member, r

2., An electrical apparatus. comprising a frame structure, a shaft journaled in. said frame structure, a plurality of, switch conest n luding tremeoppo i e Qn ts an intermediate contact mounted. from said frame structure, a separate shaft member journaled in said frame structure, a switch armcarried by said separate, shaft member and ar anged, t stablis ne t on with: a

selected one of said contacts, and a switching lever secured to the opposite end of said separate shaft member for movement in a curved path, said lever having a portion thereof sur rounding said shaft and being limited at oppositeends of its path of movement by abutment with said shaft.

3. An electrical control apparatus comprising a frame mounted adjacent an apparatus panel, a shaft member journaled in said frame, an actuating knob securedtothe end of said shaft, a separate shaft member journaled in said frame, said'separate shaft member terminating in a position under said actuating knob normalto'the plane of the peripheral edge of said knob adjacentv said panel, a switch lever secured to-the end of said separate shaft member, said lever projecting beyond the peripheral edge of said knob and having a portion thereof surrounding said first mentioned shaft and a switching mechanism arranged to be controlled by said lever.

4. An electrical control apparatus comprising a frame structure, a shaft journaledi in said frame structure, an actuating knob secured to the end of said shaft, an insulated panel supported from said frame structure, a plurality of contacts on, said panel including contacts adjacent opposite ends of said panel and an intermediate contact, a movable switching device arranged to establish connection with a selected one of said contacts, said movable switching device being positioned within the area of said actuating knob and having a portion thereof surrounding said shaft whereby the path of travel of said switching device is limited by abutment with opposite sides of said shaft.

5. An electrical control apparatus comprising a frame structure, a shaft journaled in said frame structure, an actuating knob secured to the end of said shaft, a plurality of electrical contacts including opposite remote contacts and an intermediate contact supported from said frame structure, an independent shaft member journaled in said frame structure, said independent shaft member carrying a switch blade arranged to sweep over said contacts and a lever secured to the outer end of said independent shaft member, said lever being positioned in a plane parallel with the under-surface of said knob and extending on opposite sides of said first mentioned shaft whereby angular displacements of said lever effectcorresponding movement of said switch blade with respect tosaid contacts over a path of travel limited by the abutment of said: lever with opposite sides 0 said first mentioned shaft.

6. In an electrical apparatus, a: framestructure, a; shaft journaled in said frame structure, an actuating knohsecured to theend of said shaft, a plurality of electrical contacts supported from said frame structure including contacts, adjacent. each end ofsaid, frame structure and intermediate the ends thereof, a second shaft journaled in said frame structure and carrying a switch blade on one end thereof for establishing connection with said contacts, and an actuating lever on the other end thereof, said actuating lever being apertured intermediate the ends thereof with the apertured portion surrounding said first mentioned shaft whereby angular displacement of said actuating lever in a plane parallel with the under-surface of said actuating knob effects corresponding movement of said switch blade.

7. In an electrical control apparatus a frame structure, a shaft journaled in said frame structure, an actuating knob secured to the end of said shaft, a plurality of contacts supported from said frame structure adjacent opposite ends of said frame structure and intermediate the ends thereof, a separate shaft journaled in said frame structure adjacent said first mentioned shaft, said separate shaft having a switch blade at one end thereof for establishing connection with a selected one of said contacts, an actuating lever secured to the other end of said separate shaft for swinging movement in a plane parallel to the under-surface of said actuating knob, said actuating lever extending beyond the periphery of said knob and being enlarged and apertured intermediate the ends thereof for surrounding said first mentioned shaft whereby movement of said actuating lever may be effected throu h a limited angular distance for selecting t e position of said switch blade with respect to said contacts between limits established by abutment of the apertured portion of said lever with the opposite sides of said first men- 0 tioned shaft.

In testimony whereof I afiix my signature.

WILLIAM M. BROWER. 

